[OnePlus 3T ROMs, Kernels, Recoveries, & Other Deve] :
Do I? Where? I'm pretty sure (near to absolute) I'm not using CyanogenMod repos, because:

ingo@adler /usr/local/src/cm14/frameworks/base $ git remote -v |grep -i cyanogen
ingo@adler /usr/local/src/cm14/frameworks/base $ git remote -v |grep -i lineage
los https://github.com/LineageOS/android_frameworks_base (fetch)
los https://github.com/LineageOS/android_frameworks_base (push)
ingo@adler /usr/local/src/cm14/frameworks/base $ git branch -av |grep los/
remotes/los/cm-14.1 90c2139b120 Fix security hole in GateKeeperResponse.
ingo@adler /usr/local/src/cm14/frameworks/base $ git lg1|head -n62
* 502975c5dd6 - (vor 13 Tagen) Add translation for Dash Charging — crian (HEAD -> nlos-14.1, nvertigo/nlos-14.1, m/cm-14.1, github/nlos-14.1)
* 8d92774cc6a - (vor 4 Wochen) LICENCE: add additional NLOS and NLOS-Artwork licences. — nvertigo
* 34f4223648b - (vor 4 Wochen) Add default NLOS wallpaper. — osamaaamer95
* a482b4034a7 - (vor 5 Monaten) Fix permissions for CTS [1/2] — Shane Francis
* 935cde6af29 - (vor 11 Monaten) OMS: StrictMode and files under /data/system/theme/ — mickybart
* 4a489cf2681 - (vor 6 Monaten) Add protected broadcast for app crash broadcast — Ivan Iskandar
* aaf571d90b7 - (vor 1 Jahr, und 9 Monaten) Themes: Allow volume slider and thumb to work with custom images. — Randall Rushing
* 913ab2299e3 - (vor 6 Monaten) Separate tile label color from icon drawable color — bigrushdog
* 29e656ee737 - (vor 7 Monaten) Hold "volume up" during boot to disable all overlays — George G
* e34fc9f7228 - (vor 6 Monaten) Themes: Expose Keyboard Shortcuts Dialog — Bryan Owens
* 374d897d57f - (vor 7 Monaten) Expose Screenshot flash and background colors — ezio84
* 16da9f51223 - (vor 7 Monaten) ThemeSafety: Introduce App Crash Intent — Ivan Iskandar
* 761c7947008 - (vor 7 Monaten) Revert "Add a protected broadcast for Masquerade events" — Nathan Chancellor
* 958ae3f7c89 - (vor 7 Monaten) base: Force authorize all calling packages by Masquerade (2/3) — George G
* 588df107fbc - (vor 7 Monaten) FWB: Give power dialogs own set of volume icons for themes — Bryan Owens
* 5bdd5b0c8fa - (vor 7 Monaten) OMS: Add hide annotation to MODIFY_OVERLAYS permission — Evan Anderson
* aecc650e0de - (vor 7 Monaten) OMS7: Rootless Security Update Preparation for March 2017 — Nicholas Chum
* bcc788918f2 - (vor 9 Monaten) Add a protected broadcast for Masquerade events — bigrushdog
* 7be34cc81e4 - (vor 8 Monaten) Notification tint: add optional findContrastColor algorithm for dark backgrounds — SpiritCroc
* 31708d6d616 - (vor 8 Monaten) Themes: Expose Keyguard affordance circle background — Branden M
* 6079b15122b - (vor 8 Monaten) Set external QS tiles tint mode to SRC_ATOP — Alex Cruz
* 8cc9a1b5448 - (vor 8 Monaten) graphics: ADB "N" icon compatible with OMS7 — George G
* 133b7991750 - (vor 8 Monaten) Expose external qs tile tint color — Alex Cruz
* 76e32029b75 - (vor 9 Monaten) SystemUI: Expose switch bar title — daveyannihilation
* f354e6f1c5e - (vor 10 Monaten) OMS: Introduce MODIFY_OVERLAYS permission for user apps — bigrushdog
* b7c3131bf8e - (vor 12 Monaten) Themes: Expose QS battery — Abdulwahab Isam
* 517cf57e189 - (vor 10 Monaten) OMS7-N: ApplicationsState: add filter for Substratum icon overlays [1/2] — Kuba Schenk
* 61755e2b67f - (vor 1 Jahr, und 3 Monaten) OMS7-N: ApplicationsState: add filter for Substratum overlays [1/2] — George G
* 86a2c28b64b - (vor 10 Monaten) SystemUI: Use own drawables for QS expand icon — Ivan Iskandar
* 64dffe5ae06 - (vor 1 Jahr) doze: allow grayscale even if invert boolean is false — Daniel Koman
* 525060af32b - (vor 11 Monaten) OMS7 compatible 'Ambient notification inversion' — George G
* 6af01a3b005 - (vor 2 Jahren, und 6 Monaten) Allow prevention of doze notification color inversion — Daniel Koman
* 657b78fa123 - (vor 11 Monaten) Notification dynamic colors bool compatible with OMS7 — George G
* 1353c4f7daf - (vor 1 Jahr, und 1 Monat) Notifications: Expose a bool to disable dynamic colors — Nicholas Chum
* 4764bfa536d - (vor 1 Jahr) Themes: Expose various QuickSettings text colors — Niklas Schnettler (Sh4dowSoul)
* 64b6d5967ef - (vor 10 Monaten) Allow custom alpha for notification shade bg color — Simao Gomes Viana
* c2faf42444c - (vor 1 Jahr, und 1 Monat) SystemUI: Expose QS edit item decoration background color — Ivan Iskandar
* 71910cb76a6 - (vor 1 Jahr, und 6 Monaten) Themes: Allow Navbar ripple color to be themed — Dave Kover
* 6aa2a9c45c0 - (vor 1 Jahr, und 10 Monaten) Themes: Allow Permission Icons to be fully themed — Nicholas Chum
* 1d3cc1181cd - (vor 1 Jahr, und 11 Monaten) Themes: Allow Immersive cling colors to be fully themed — Nicholas Chum
* 5ce7807761d - (vor 10 Monaten) Themes: Expose resolver hardcoded colors — Dave Kover
* 698741e5c44 - (vor 1 Jahr, und 3 Monaten) N-Extras: AudioService: Allow system effect sounds to be themed — Nicholas Chum
* 4a09092ec88 - (vor 1 Jahr, und 3 Monaten) N-Extras: Add dynamic theme fonts support — 0xD34D
* c567aa3ab93 - (vor 1 Jahr, und 4 Monaten) N-Extras: Add dynamic theme BootAnimation support — 0xD34D
* 786af0189e8 - (vor 1 Jahr, und 3 Monaten) OMS7-N: Implement multi-target enable/disable and disable-all [11/11] — Jacob McSwain
* b61a4c1b06b - (vor 11 Monaten) OMS7-N: Do not enforce code policy limiting overlay installation [10/11] — Nicholas Chum
* 75a3bc4d67d - (vor 1 Jahr, und 4 Monaten) OMS7-N: Persistence on boot through OverlayManagerServiceImpl [9/11] — Nicholas Chum
* 6e46684c523 - (vor 7 Jahren) OMS7-N: Disable Zygote preloaded drawables [8/11] — Josh Guilfoyle
* b3b3d071cae - (vor 1 Jahr, und 4 Monaten) OMS7-N: installd: add command 'rmidmap' [7/11] — Mårten Kongstad
* 8fbd8062e40 - (vor 1 Jahr, und 4 Monaten) OMS7-N: Fix memory leak during idmap creation [6/11] — Mårten Kongstad
* dc168e76a82 - (vor 1 Jahr, und 7 Monaten) OMS7-N: idmap: suppress print for padded resources [5/11] — Mårten Kongstad
* fe318089872 - (vor 1 Jahr, und 5 Monaten) OMS7-N: Set EXTRA_REPLACING correctly in ACTION_PACKAGE_ADDED [4/11] — Mårten Kongstad
* 8e5516b4cfb - (vor 1 Jahr, und 4 Monaten) OMS7-N: Integrate OverlayManagerService into framework [3/11] — Mårten Kongstad
* 5a3ab9ba9c7 - (vor 1 Jahr, und 10 Monaten) OMS7-N: Introduce the OverlayManagerService [2/11] — Mårten Kongstad
* e74dcdc92e2 - (vor 1 Jahr, und 10 Monaten) OMS7-N: Support tagging resources as OK to overlay [1/11] — Mårten Kongstad
* 8e8df27e757 - (vor 6 Monaten) Fingerprint: Speed up wake-and-unlock scenario — Sultanxda
* 7eb093e6c6a - (vor 12 Monaten) telephony: Hack GSM and LTE signal strength — Sultanxda
* 73b24ee1ac4 - (vor 5 Monaten) BatteryService: add dash charging support — thecrazyskull
* 27220c4cf03 - (vor 2 Jahren, und 10 Monaten) SystemUI: Network Traffic [1/3] — Jon Haus
* 734141d2107 - (vor 6 Monaten) Allow location providers also outside of /system. — danielegobbetti
* 4d88403c240 - (vor 1 Jahr, und 3 Monaten) Add signature Spoofing permission — Benoît Mauduit
* 90c2139b120 - (vor 3 Monaten) Fix security hole in GateKeeperResponse. — Charles He (los/cm-14.1)

As you can easily see with the lg1 alias, there is no merge, fork or anything. Our changes are applied on top of official lineageos source tree. I strongly recommend using lg1 on the commandline, to understand what is in the history of one or more branches and repos. In my previous posting I showed how to have more then one remote repos in a local repo. If you look at my chagall and exynos gits, you'll see, that the comp,ete history from cm-11.0 on is maintained with all branches - current is lineageos cm-14.1 baesed.