when i look at the memory map of the dive profile in my ostc there ist something strange.
The documentation say a dive starts with 0xFA 0xFA and ends with 0xFD 0xFD so far so good.
Before the first dive i cleaned my logbook (maybe this is the reason).
The memory dump says
Byte 00267 - 31499 = 0xFF
Then
Byte 31500 0xFD 0xFD
Byte 31502 0xFA 0xFA 0x20 0x06 0x05 0x0B 0x0C 0x01
The real profile ends at the memory end with byte 33034
This is the only profile where the dive ends after 31232 0xFF bytes.
The other dives i have, form a friends OSTC, end at memoryend with 0xFD 0xFD
and at the last position, byte 33034 with 0xFE
and not, as my dive directly before the divestart and
without the 0xFE so i have no last dive?
Maybe im still diving and didn't recognize that.

Both OSTC with version firmware 1.90.
My OSTC
Dive start found at 31502
Date of dive: 05.06.2011
Dive end found at 31500
Lastdive byte 0xFE not found
my friends OSTC
Dive start found at 28430
Date of dive: 09.05.2011
Dive end found at 29266
Dive start found at 29268
Date of dive: 29.05.2011
Dive end found at 30923
Dive start found at 30925
Date of dive: 02.06.2011
Dive end found at 33032
Lastdive byte 0xFE found at 33034
Best regards
Rob