If you apply while she is still in Egypt your application will require more paperwork on your part. With her out of the country you will have to provide proof that she will be returning to Canada and also proof that she can support the 2 of you when you arrive in Canada. Read the application closely, there are questions that apply to a sponsor living and applying from outside Canada. You might consider to wait for her to arrive back in Canada before submitting the app. It would simplify your app if you wait until June.
It's a good point that a Canadian citizen residing abroad does need to provide more information and whether it is preferable to submit right away or to wait the couple of months to return to Canada and then submit - no-one can say.
Personally I would submit earlier if not too difficult - and provide some information about plans to return to Canada. But I say that without knowing much about the couple and their background, and it may depend on all that relationship history etc as well as what documentation is easily available.
Some factors to consider in deciding:
-since the couple has been married for only a relatively short while (how long have they known each other?), 'residing together' does provide some additional support for the relationship.
-if the sponsor has maintained a fair number of 'residential' links (eg some of residential address to return to and reside in, bank account, employment history, telephone number, family in Canada, etc), the plane tickets to return may be pretty decent evidence of 'intent to return.'
-if in contrast the sponsor has few or zero links to Canada, demonstrating that intent to return may be a bit more difficult and the plane ticket
alone may be a bit weak.
-As noted, in any case, the sponsor should definitely update IRCC of the return to Canada once physically in Canada (address in Canada, updated contact info, and employment when possible).
-Note that in all cases the sponsor is expected to show ability to support (even if no specific income requirement), which can be savings, employment plans, and - for the citizen-abroad - the PA's plans for employment as well.
-The 'rub' is that for a citizen-in-Canada-sponsor they seem to usually expect the tax return info and/or actual employment (whereas the Canadian abroad is clearly not employed in Canada - usually) and may need some additional explanation. This may not mean a lot of extra scrutiny for one who has just returned and not yet found employment - I don't know. But my point is it's a bit of a trade-off and not clear whether applying first from abroad is actually better or worse than waiting and applying a few months later. (Then there's the uncertainty of covid and whether plans end up changing for reasons beyond the control of the couple)
On the other hand, if the sponsor has
only the plane ticket as evidence of intent to return and no other significant ties in Canada, that would be pretty weak.
So, it's up to the OP. I stated my
slight preference based on very little information (and should be adjusted if very different, eg a Canadian citizen who has never resided in Canada might think more carefully). But if the OP actually does return to Canada soon as planned and updates IRCC on arrival, I doubt this aspect alone would be determinative.