[Google Pixel 2 XL Guides, News, & Discussion] joedeuce:
Ok, so when I send that payload with OPEN and get a list of partitions, I get a completely different set of partitions:

With payload:

MBR Header
LBA size (sector size): {0} 512
Number of MBR partitions: 1
# Active From(#s) Size(#s) Code Type
1 _ 1 4294967295 EE EFI GPT protective MBR
GPT Header
Disk GUID: 25C6DACF-4929-0791-2561-11DD6D31D595
LBA size (sector size): 4096
GPT First LBA: 1
GPT Last LBA: 352255
Number of GPT partitions: 41
# Flags From(#s) To(#s) GUID/UID Type/Name
1 1169528528232775680 6 133 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
C10B1D19-66CF-74E3-B7C8-B389EBCEE6BB rpm_a
2 1169528528232775680 134 645 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
0EBEDB79-B75D-53A2-5899-B1A54C6953F0 tz_a
3 16607023625928704 646 773 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
4B0C8E23-EBDE-A83F-46C7-55CF94D65A6D hyp_a
4 16607023625928704 774 901 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
F2265DAA-E9DA-0FB5-A35E-46A938B39D46 pmic_a
5 1169528528232775680 902 21381 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
346C04AB-6759-9CB7-952A-760545DE11EC modem_a
6 1169528528232775680 21382 21637 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
45F34940-0FF1-7F74-D1B7-83F5FDC881BD abl_a
7 1169528528232775680 21638 21765 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
B96F676A-6362-3E48-D546-88C1153C9A76 keymaster_a
8 36591746972385280 21766 32005 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
3D0E7F57-141D-D963-275C-5FFAA68B93AA boot_a
9 1169528528232775680 32006 32133 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
A48ED622-8BBC-075A-8884-66598D83E972 cmnlib_a
10 1169528528232775680 32134 32261 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
7C2058B7-8BAA-9337-CBF7-6A07F33447B6 cmnlib64_a
11 16607023625928704 32262 32293 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
77CF762D-1D83-2566-E31A-654FA05238BD devcfg_a
12 1169528528232775680 32294 32309 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
42453537-866C-AE62-B009-CB8094C79611 vbmeta_a
13 1169528528232775680 32310 34357 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
7104A397-03A3-4F15-2A71-494F29C624A9 dtbo_a
14 1169528528232775680 34358 162357 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
DC309FFC-CC20-D5D2-C183-7B53BE4E0FA1 vendor_a
15 35747322042253312 162358 162485 098DF793-D712-413D-9D4E-89D711772228 Unknown
92032EAC-E9DB-02AF-AC7D-C7F5FA41FB98 rpm_b
16 35747322042253312 162486 162997 A053AA7F-40B8-4B1C-BA08-2F68AC71A4F4 Unknown
1197827E-6B64-3BAD-FA9A-9EE2A6041F99 tz_b
17 35747322042253312 162998 163125 E1A6A689-0C8D-4CC6-B4E8-55A4320FBD8A Unknown
1CEF2D66-B9C0-C220-2A4E-19E78E4E78F7 hyp_b
18 35747322042253312 163126 163253 C00EEF24-7709-43D6-9799-DD2B411E7A3C Unknown
9805459C-8574-0087-F298-13CC44C2E9C7 pmic_b
19 1188668826649100288 163254 183733 EBD0A0A2-B9E5-4433-87C0-68B6B72699C7 Basic data partition
B57BD1B2-C55F-539E-0B0D-B19E9315D8F2 modem_b
20 1188668826649100288 183734 183989 BD6928A1-4CE0-A038-4F3A-1495E3EDDFFB Unknown
D9E51C25-77B6-B217-2CF8-7F52A26E7887 abl_b
21 1188668826649100288 183990 184117 A11D2A7C-D82A-4C2F-8A01-1805240E6626 Unknown
5BB6ADE4-934F-61D9-EFE0-427972F4B7AA keymaster_b
22 1970324836974592 184118 194357 20117F86-E985-4357-B9EE-374BC1D8487D Unknown
BFD58B29-9BC0-1707-F1AF-64D18F7FD4A1 boot_b
23 1188668826649100288 194358 194485 73471795-AB54-43F9-A847-4F72EA5CBEF5 Unknown
FDD2833F-5F4E-F7CC-61B6-2D11B0E2CBA5 cmnlib_b
24 1188668826649100288 194486 194613 8EA64893-1267-4A1B-947C-7C362ACAAD2C Unknown
978F161D-70F2-4F62-7C4E-9F0D59F31E60 cmnlib64_b
25 35747322042253312 194614 194645 F65D4B16-343D-4E25-AAFC-BE99B6556A6D Unknown
EA25CC97-3776-C451-4567-3EA581E43D72 devcfg_b
26 1188668826649100288 194646 194661 4599BD31-F0DC-48A0-9C56-B8C969F3E1D2 Unknown
DDF752DC-4C9B-089B-416F-D55D13EA19B7 vbmeta_b
27 1188668826649100288 194662 196709 3305B8D9-07DF-4547-8E77-8D58ADE95826 Unknown
6916BABF-2770-9FCB-AF1F-2CD75448FC8C dtbo_b
28 1188668826649100288 196710 324709 97D7B011-54DA-4835-B3C4-917AD6E73D74 Unknown
C862DC98-7D27-F89B-4CA8-58B97582823C vendor_b
29 0 324710 324773 E6E98DA2-E22A-4D12-AB33-169E7DEAA507 Unknown
7BF95EA2-A541-6B08-BE05-CD7E4E9AF982 apdp
30 0 324774 324837 ED9E8101-05FA-46B7-82AA-8D58770D200B Unknown
E43D756A-9EA5-5448-B82C-1F96FE17BE7D msadp
31 1152921504606846976 324838 324869 02DB45FE-AD1B-4CB6-AECC-0042C637DEFA Unknown
E8964687-FC4E-AAC0-69DE-CEFBBF7DD679 storsec
32 1152921504606846976 324870 325381 638FF8E2-22C9-E33B-8F5D-0E81686A68CB Unknown
101AE9A7-E7BF-0EB4-6D8D-3173AD9D667A fsg
33 1152921504606846976 325382 325413 303E6AC3-AF15-4C54-9E9B-D9A8FBECF401 Unknown
D0065A7F-3DCB-68C2-3D9B-0254978206AB sec
34 1152921504606846976 325414 325414 65ADDCF4-0C5C-4D9A-AC2D-D90B5CBFCD03 Unknown
0084694A-FDEB-659D-4EBE-2BAB67FFDF7A devinfo
35 1152921504606846976 325415 325670 4114B077-005D-4E12-AC8C-B493BDA684FB Unknown
A1862F6F-14B5-B921-785C-3B9AC0B6E1CE dip
36 0 325671 325671 11406F35-1173-4869-807B-27DF71802812 Unknown
F61967E0-FC4E-E8D6-A89D-87B663836F92 dpo
37 1152921504606846976 325672 325672 10A0C19C-516A-5444-5CE3-664C3226A794 Unknown
97B649DD-C39B-D6E2-0D32-CD06E8CA40CC limits
38 1152921504606846976 325673 325928 97745ABA-135A-44C3-9ADC-05616173C24C Unknown
45938DC4-E3B0-CC91-2977-0EF11C6FDE60 toolsfv
39 0 325929 327976 BC0330EB-3410-4951-A617-03898DBE3372 Unknown
2293FB4E-9A2C-5B6E-B68B-857C44F090EA logfs
40 0 327977 328488 AA9A5C4C-4F1F-7D3A-014A-22BD33BF7191 Unknown
13E04A96-1F57-7135-6BD2-B0CFB67244FA sti
41 0 328489 332584 903BB98C-9776-428F-B805-4C276A63E136 Unknown
1579CB48-43E9-721E-5A4E-75704D699D68 metadata

Without payload:

MBR Header
LBA size (sector size): {0} 512
Number of MBR partitions: 1
# Active From(#s) Size(#s) Code Type
1 _ 1 4294967295 EE EFI GPT protective MBR
GPT Header
Disk GUID: E7AC4884-8EF5-FA98-BB09-2F73881A5E52
LBA size (sector size): 4096
GPT First LBA: 1
GPT Last LBA: 15258623
Number of GPT partitions: 13
# Flags From(#s) To(#s) GUID/UID Type/Name
1 16607023625928704 6 12293 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
A402A7B8-28F9-5689-0825-4A1CC1B80A8B laf_a
2 35747322042253312 12294 24581 98523EC6-90FE-4C67-B50A-0FC59ED6F56D Unknown
59CFDC38-F1D6-D7E6-604A-22116866D591 laf_b
3 0 24582 24583 2C86E742-745E-4FDD-BFD8-B6A7AC638772 Unknown
9CD17022-A030-C6D6-95A3-9D8598CA5FC7 ssd
4 0 24584 32775 6C95E238-E343-4BA8-B489-8681ED22AD0B Unknown
F81179B4-FADC-8FBC-25AE-ECA5D3567734 persist
5 0 32776 33031 82ACC91F-357C-4A68-9C8F-689E1B1A23A1 Unknown
15C0ACC1-9975-A5EA-D8BA-518F973F7471 misc
6 0 33032 41223 DAA3EAAC-9D97-4EFF-A9B5-6BAF57D1495E Unknown
2A30FBBD-A378-2F07-2506-453E27BD34E2 ftm
7 16607023625928704 41224 696583 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
0309BC82-B632-A167-B43A-DA33F8CC51DA system_a
8 35747322042253312 696584 1351943 97D7B011-54DA-4835-B3C4-917AD6E73D74 Unknown
4D1438D1-73D4-E47D-7089-942E075A8702 system_b
9 0 1351944 1353991 025064E1-D2A2-44C6-9626-67E374C08EAB Unknown
AB71D407-B75C-B75E-D553-140975E84975 pstore
10 16607023625928704 1353992 1354119 77036CD4-03D5-42BB-8ED1-37E5A88BAA34 Unknown
3937BB70-D69A-D0B9-C260-84202DFEC1E2 aes_a
11 35747322042253312 1354120 1354247 BD9E4B34-E2F3-49FC-920D-BCCBDF3D4710 Unknown
554FEF57-3995-A08D-2077-D5EB54BF6BFD aes_b
12 0 1354248 1355775 0A7BE037-F315-4166-B2C2-851B004C696B Unknown
20150724-892E-4FAB-2AC6-43423CD3369F align_parti
13 0 1355776 15258618 1B81E7E6-F50D-419B-A739-2AEEF8DA3335 Unknown
EE44D4D0-4796-279E-EA96-5459B216B5AB userdata

I'm sure there is a simple explanation.