If you didnt receive the ITA yet and if you receive on the last day of your PGWP expiry better gather all the docs ready so that you can submit application same day and also mostly the AOR will be sent in an hour sometimes it may get delay like 24hrs.But meanwhile you can get ready with the BOWP application to submit so once you get the AOR you can attach and submit the BOWP application.You will be on implied status until they make a decision once the decision is positive well and good if not you have to either apply for visitor visa and stay in the country (but cannot work) or else go back home and come back when the PR processing is completed.I dont know about ppl having dependent spousal applicant but all of this process is for an individual.if you didnt get the ITA even on the last day of your permit you cant apply for BOWP to apply for that you need to have AOR which u will get once you submit PR application with supporting docs. In CIC website it says in worst they can accept 30 days grace period after expiry of work permit but it will be allowed only on the case of any other Visa application is processing or under review and you have been waiting but in your case it doesnt get into account so you cant stay after your permit expiry if no ITA is going to be received.Hopefully this week they may take another CEC draw and score may drop below 440.the only option to apply work permit ext.besides the above process is if your employer provided LMIA which i guess in your case no otherwise you would have got ITA by now with LMIA(50 points additional).