For the probability that this is the beginning of the message see introduction. If this is correct we might expect it to begin with a name or names (cf. 295.i.3, 300.i.3). The traces of 8-9 letters at the left might end with -um.
comm...[: it is difficult to envisage any restoration other than commili[tones/onem (cf. 226.c.4 note) and there is room to restore it, assuming that we have a left-hand column. If this is correct it is possible to imagine that it was written by an auxiliary prefect, cf. Suetonius, Caes. 67.2, nec milites eos pro contione, sed blandiore nomine commilitones appellabat. Alternatively, it might have come from a centurion commanding a cohort in a legion (see Breeze (1969) and cf. 255.back 20 note).
missi: see 255.i.6-8 note, 309.i.3 note.
poss[: poss[is is the likeliest restoration but we cannot exclude poss[im. There are no tops of letters visible below this line, which suggests that the letter was a short one with not more than 5 lines in this column.