What is considered a standard time for asking a status update from the editor for various stages of peer-review?
I can see two reasons where asking for a status update is any reasonable:

You have a practical use for the information, i.e., it would actually affect a relevant decision you make. For example, when you know that the journal is only waiting for one reviewer who is trustworthy and promised to submit a report next week, you would not plan a lengthy vacation so you can react to the decision. If you just want a prognosis to soothe your impatience or similar, that’s not a practical use.

Things are taking too long and you hope that nudging the editors will get them to take relevant action such as reminding reviewers. Mind that this is too long with respect to the standards of the field and journal, not your own time constraints. For details and particular what is too long, see: Is my paper under review (or similar) for too long and if yes, how should I react?.


In particular, there is no reason to expect that asking for status updates is accelerating anything unless Point 2 applies. It’s like repeatedly pushing the crosswalk button.
If you want to communicate something to the editors, do it explicitly (and not implicitly by sending frequent status requests).
Specifically, just tell them why it is crucial for you to have a decision on this paper within whatever your deadline is.
Even then, this will likely not considerably accelerate the process or ensure anything, but at least the editors might give you a prognosis as to how likely they will be in time or tell you when it becomes evident that they cannot make a decision in time.

Hence it is extremely important to get review within a stipulated time

First, are you sure? You can usually already search for postdoc positions and similar without your PhD being actually completed. Second, just that it is important does not mean that you can do something about it. Sometimes, things are just a matter of luck; this is usually one of those cases.