I don’t like breaking the fourth wall too often, but I’m not above doing it.

This is actually a question that us Webcomic artists have to tackle every so often. Especially in comics that describe day-to-day life in modern day times as opposed to a big storyline with a beginning, middle, and end, or something that takes place in a different timeline.

Each comic artist tends to tackle it differently.

Some creators issue the “Time Freeze”. It’s always the same time. This is mostly true in summer-based TV shows such as Gravity Falls or Phineas & Ferb, where it’s never NOT summer.

Some keep it vague, where time seems to go by but no real changes occur.

Some creators stream time normally, it’ll be the same date in the comic as it is in reality. This comes with some issues as, if you have a particularly long storyline you could end up seeing Halloween, thanksgiving, Christmas and new year’s all taking place inside it. It connects better to reality but it could end up weird if you don’t know how to control it, and your characters could end up aging really fast if you let them. “Girls With Slingshots” tends to take this route.

Some creators slow time down. Way down. The plot comes first, time progression is secondary. If that means the comic falls out of sync with reality, so be it. “Leftover Soup“, which is a great webcomic, does this. It does this so heavily, in fact, that even though it’s been running for about 4 years now, in-world it’s only been about a month, if not less.

Over the years (This includes future comics which have yet to be translated into English) Dueling Grannies has taken all these routes.
It started off vaguely unstuck in time. Things progressed in the world, but there wasn’t anything going in-world anyway.
Then I decided to let time progress normally (I even kind of sped it up at some point, letting things happen faster than they would have otherwise, specifically to age Jonathan up), and in the comics I’m doing now time has slowed down to a crawl (or even a freeze, if you will), because if I hadn’t slowed it down they would have graduated and gotten enlisted in the army by now, an experience I have little to no desire to write about.

I already have plans for what happens after that, but you’ll have to wait and see.