V13 has been in development since shortly after V12's release, so that's uh... well over 1 1/2 year by now, creeping closer to the 2 year mark even.
Granted the scope for V13 ended up being way bigger than expected (what with it turning out to be the biggest update to the game since V6) and there's been a ton of various outside influences causing delays (Gen 8 project, Covid, Jan falling sick for a while etc.), which is why the decision was made to split all the side content from the main update as a separate patch to lessen the workload for main release, and even with THAT put to the side for now everything turned out to be a lot more work than expected, so yyyyyyyyyyyeah uh. Even with all the delays, this version had so much work invovled that it would never end up being a short dev cycle in the first place.
This update's amount of content is basically multiple versions in one, there was and STILL is a lot left to be done, but the project never was truly at a standstill and just went incredibly slow for a long time due to stuff outside of our control.
We're finally getting close to the end of the dev cycle though if the status bars don't already suggest as much, so hopefully it's not going to be a very long wait anymore!!