[Verizon LG G3] PiousInquisitor:
You checked the 'Total space' before moving to CM12 right? What was it? 30.8?

Its probably adb time. Check out your partition table and see if there is anything odd. You may want to be on stock so we can compare.

Please run:

adb shell cat /proc/partitions

You should see something similar to this:

major minor #blocks name

179 0 30535680 mmcblk0
179 1 65536 mmcblk0p1
179 2 1024 mmcblk0p2
179 3 512 mmcblk0p3
179 4 512 mmcblk0p4
179 5 2048 mmcblk0p5
179 6 1024 mmcblk0p6
179 7 1024 mmcblk0p7
179 8 4 mmcblk0p8
179 9 1024 mmcblk0p9
179 10 512 mmcblk0p10
179 11 1024 mmcblk0p11
179 12 1024 mmcblk0p12
179 13 1024 mmcblk0p13
179 14 1024 mmcblk0p14
179 15 512 mmcblk0p15
179 16 2048 mmcblk0p16
179 17 2044 mmcblk0p17
179 18 16384 mmcblk0p18
179 19 32768 mmcblk0p19
179 20 16384 mmcblk0p20
179 21 3072 mmcblk0p21
179 22 3072 mmcblk0p22
179 23 4 mmcblk0p23
179 24 3072 mmcblk0p24
179 25 512 mmcblk0p25
179 26 512 mmcblk0p26
179 27 4 mmcblk0p27
179 28 512 mmcblk0p28
179 29 512 mmcblk0p29
179 30 8 mmcblk0p30
179 31 5104 mmcblk0p31
259 0 16384 mmcblk0p32
259 1 32768 mmcblk0p33
259 2 32768 mmcblk0p34
259 3 16384 mmcblk0p35
259 4 8192 mmcblk0p36
259 5 8192 mmcblk0p37
259 6 32768 mmcblk0p38
259 7 8192 mmcblk0p39
259 8 24576 mmcblk0p40
259 9 16384 mmcblk0p41
259 10 2949120 mmcblk0p42
259 11 868352 mmcblk0p43
259 12 26340858 mmcblk0p44
259 13 501 mmcblk0p45
179 32 4096 mmcblk0rpmb
179 64 30703616 mmcblk1
179 65 30699520 mmcblk1p1

Then run this to show what partitions are what:

adb shell ls -la /dev/block/platform/msm_sdcc.1/by-name/

You should see something similar to this:

lrwxrwxrwx root root 1970-05-21 19:57 DDR -> /dev/block/mmcblk0p4
lrwxrwxrwx root root 1970-05-21 19:57 aboot -> /dev/block/mmcblk0p5
lrwxrwxrwx root root 1970-05-21 19:57 abootf -> /dev/block/mmcblk0p16
lrwxrwxrwx root root 1970-05-21 19:57 boot -> /dev/block/mmcblk0p18
lrwxrwxrwx root root 1970-05-21 19:57 cache -> /dev/block/mmcblk0p43
lrwxrwxrwx root root 1970-05-21 19:57 dbi -> /dev/block/mmcblk0p3
lrwxrwxrwx root root 1970-05-21 19:57 dbibak -> /dev/block/mmcblk0p10
lrwxrwxrwx root root 1970-05-21 19:57 drm -> /dev/block/mmcblk0p36
lrwxrwxrwx root root 1970-05-21 19:57 eksst -> /dev/block/mmcblk0p29
lrwxrwxrwx root root 1970-05-21 19:57 encrypt -> /dev/block/mmcblk0p28
lrwxrwxrwx root root 1970-05-21 19:57 eri -> /dev/block/mmcblk0p39
lrwxrwxrwx root root 1970-05-21 19:57 factory -> /dev/block/mmcblk0p40
lrwxrwxrwx root root 1970-05-21 19:57 fota -> /dev/block/mmcblk0p34
lrwxrwxrwx root root 1970-05-21 19:57 fsc -> /dev/block/mmcblk0p25
lrwxrwxrwx root root 1970-05-21 19:57 fsg -> /dev/block/mmcblk0p24
lrwxrwxrwx root root 1970-05-21 19:57 grow -> /dev/block/mmcblk0p45
lrwxrwxrwx root root 1970-05-21 19:57 laf -> /dev/block/mmcblk0p33
lrwxrwxrwx root root 1970-05-21 19:57 misc -> /dev/block/mmcblk0p32
lrwxrwxrwx root root 1970-05-21 19:57 modem -> /dev/block/mmcblk0p1
lrwxrwxrwx root root 1970-05-21 19:57 modemst1 -> /dev/block/mmcblk0p21
lrwxrwxrwx root root 1970-05-21 19:57 modemst2 -> /dev/block/mmcblk0p22
lrwxrwxrwx root root 1970-05-21 19:57 mpt -> /dev/block/mmcblk0p38
lrwxrwxrwx root root 1970-05-21 19:57 operatorlogging -> /dev/block/mmcblk0p41
lrwxrwxrwx root root 1970-05-21 19:57 pad -> /dev/block/mmcblk0p8
lrwxrwxrwx root root 1970-05-21 19:57 pad1 -> /dev/block/mmcblk0p23
lrwxrwxrwx root root 1970-05-21 19:57 pad2 -> /dev/block/mmcblk0p27
lrwxrwxrwx root root 1970-05-21 19:57 persist -> /dev/block/mmcblk0p19
lrwxrwxrwx root root 1970-05-21 19:57 rct -> /dev/block/mmcblk0p30
lrwxrwxrwx root root 1970-05-21 19:57 recovery -> /dev/block/mmcblk0p20
lrwxrwxrwx root root 1970-05-21 19:57 rpm -> /dev/block/mmcblk0p6
lrwxrwxrwx root root 1970-05-21 19:57 rpmbak -> /dev/block/mmcblk0p11
lrwxrwxrwx root root 1970-05-21 19:57 rpmf -> /dev/block/mmcblk0p13
lrwxrwxrwx root root 1970-05-21 19:57 sbl1 -> /dev/block/mmcblk0p2
lrwxrwxrwx root root 1970-05-21 19:57 sbl1b -> /dev/block/mmcblk0p9
lrwxrwxrwx root root 1970-05-21 19:57 sdif -> /dev/block/mmcblk0p15
lrwxrwxrwx root root 1970-05-21 19:57 sns -> /dev/block/mmcblk0p37
lrwxrwxrwx root root 1970-05-21 19:57 spare1 -> /dev/block/mmcblk0p17
lrwxrwxrwx root root 1970-05-21 19:57 spare2 -> /dev/block/mmcblk0p31
lrwxrwxrwx root root 1970-05-21 19:57 spare3 -> /dev/block/mmcblk0p35
lrwxrwxrwx root root 1970-05-21 19:57 ssd -> /dev/block/mmcblk0p26
lrwxrwxrwx root root 1970-05-21 19:57 system -> /dev/block/mmcblk0p42
lrwxrwxrwx root root 1970-05-21 19:57 tz -> /dev/block/mmcblk0p7
lrwxrwxrwx root root 1970-05-21 19:57 tzbak -> /dev/block/mmcblk0p12
lrwxrwxrwx root root 1970-05-21 19:57 tzf -> /dev/block/mmcblk0p14
lrwxrwxrwx root root 1970-05-21 19:57 userdata -> /dev/block/mmcblk0p44

Let us know what you find out.