In the texts of H/P/Q there is no parallel to Aa1-46:

Ha5-43	Ha5-44	Ha5-45	Ha5-46		Ha5-47	Ha5-48
Pa5-25	Pa5-26	Pa5-27	Pa5-28	Pa5-29	Pa5-30	Pa5-31
Qa5-33	Qa5-34	Qa5-35	Qa5-36	Qa5-37	Qa5-38	Qa5-39

Working with numbers we can guess that Qa5-36 alludes to 5 * 36 = 180 and that the sequence Pa5-28--31 alludes to the ordinal numbers of the nights at the end of a month. Ha5-48 can be 'read' as 5 * 48 = 240 (maybe a way to say that the 24 hours of a diurnal cycle are ending).

Disregarding these 'imaginations' it can anyhow be stated that the missing parallels to Aa1-46 presumably indicates it has a special function in A (not necessary in H/P/Q or not thought of by the creators of these texts).

The numerical type of exercise described above can be applied also to Aa1-46, and then we should remember that the total number of glyphs in Tahua is 1,334 = 46 * 29.