Ok. So as you all know immigration offices are closed until Thursday 17th. For many offices they will be absolutely chaotic on Thursday. If you can avoid going to immigration on that day then please do so.
If your entry stamp or extension finishes between now and then, then go on the 17th and be prepared to wait for a long time. You won’t be fined because of closure but will get an overstay stamp.
Friday will probably be crazy too because of the fallout of the 5 day closure.
Going to immigration early is usually a good idea for most extensions but this week if you really don’t need to go then just don’t.
If your extension or entry stamp is after the 20th then just do everyone a favour and avoid immigration.
I have no idea on the policies for all the immigration offices, but you may well find that some will turn you away if you don’t need immediate services.
TLDR : Answer Summary
Due to the closure of immigration offices until Thursday the 17th, it is advised to avoid visiting on that day if possible, as it will be chaotic. If your entry stamp or extension expires during the closure, plan to visit on the 17th but be prepared for long waits; you won’t be fined during this closure but may receive an overstay stamp. Friday will likely also be busy due to the backlog. If your visa is not expiring soon, it is best to wait and avoid the immigration office.