I trained a Pidgeot to nearly full completion of its arc (~90%) and then stopped training for a while due to a lack of stardust and the game saying my trainer level wasn't high enough. While collecting more dust, I gained at least four levels (the minimum four were due to a powerleveling push with a lucky egg). I then when to check on my Pidgeot again to see if I could power it up further, and its position on the arc now lines up around three-quarters (75%) of arc completion. The stardust/candies cost for the next power-up hasn't changed.
I know this is an odd question, but has anyone noticed the CP range that the arc is supposed to indicate a pokemon can train through move or change due to gains in trainer level?
I know that gaining trainer levels allows a person to catch stronger pokemon (or pokemon with more potential strength), but does gaining trainer levels also allow previously caught pokemon to be trained to higher levels?
I wish I had pictures to back up this question, but I didn't think this was possible until I noticed this discrepancy. I'm now starting a test for this by taking pictures of pokemon to record any changes while not being trained as I gain levels, but I feel a little crazy for thinking this could be a thing.