Dumb question about villagers moving back

[Amykins]

How do I know when the 16 villager limit has passed?

 

[Puffifish]

you know you have passed the 16 villagers cycle when that specific villager stop hanging around your main street c:

 

[Amykins]

Ah, crud...I thought it was safe for Julian to move back because I haven't seen him on Main Street for months, and he just showed up the other day. That's disheartening. :/ Thanks, though!