[Pathfinder] Monster spellcasting is one CL lower upon character reload

I've tested this across several different monsters with spellcasting abilities not gained from class levels (example: nagas, raksashas, lamias, neh-thalggus, etc). It seems like the proper CL is reflected in character sheet output and number of spells allowed when the character is first created. However, if the character is saved and opened again later, the caster level is lowered by one (including reducing spell selection and reported spell caster level on the character sheet).

This seems to only be occurring for spellcasting that is based on innate spellcasting levels granted by monster races. For example, a dark naga casts as a 7th level caster, but when the char sheet is reopened, it shows up as casting at 6th level upon reload. This even seems to be the case if the creatures take classes that add to their innate casting level (eg. if the dark naga takes a level in sorcerer before being saved and closed for the first time, he shows a proper CL of 8th, but upon being reloadad he shows a CL of 7th). However, a monster whose spellcasting abilities are solely based on class levels they've taken (example- a treant with levels in druid) seem unaffected by this bug.