H-1B Visa

My H1 Extension is in progress since Apr 2018. My 240 day work authorization period is expiring on Jan 15th. My employer will put me on Loss of Pay after that. My questions are :<br>

1). If I plan to wait for a decision on H1 extension, will I go out of status after Jan 15th and be staying illegally ?<br>
2). I have approved I140. Can I go back to India and apply H1 extension from there (in case this extn gets rejected), will this be considered cap exempt ?

1. I have approved I-140, on 7th yr of extension and my current H1B Visa and I-94 valid with emp A until dec 31,2018 based on my latest approval I received in Nov 1st week.
I have another 1 month to apply for an extension and I am requesting my employer to apply in premium processing.

1)If my extension is applied in Premium before I-94 expiration but pending beyond my expiration date 12/31/2018,
I will be 'out of status' even though 'authorized to stay' until decision is made. Is this correct that this may affect my future H1bs in case it is denied
and attract NTA(notice to appear) in future because of my 'out of status' from date of expiration to date of denial or while leaving the country upon denial.<br>
2. Is it better if I leave the country on the last day of my I-94 expiration(Dec 31, 2018) while my H1B extension is pending in order to avoid 'out of status' or 'unlawful presence' scenarios by staying here.
If I leave the country while extension is pending in above scenario, is it possible for me to go for consular processing, get VISA stamped after it is approved and enter the US legally?
or
is h1b extension is considered as abandoned?

I am exploring an option to move to Canada temporarily in order to save my Canadian PR. My PD date is March 2012 and have an approved I140. Currently my H1B extension based on approved I140 is in process and hopefully it shall come soon and will be good till Feb 2022. Plan is to move to Canada after H1B approval and H1B visa stamping from India. <br>
Questions<br>
1. If Priority date becomes current during my stay in Canada then what are my options.<br>
2. If Priority date does not become current and I tried to enter US after staying for more than year outside US. Two situation could occur H1B extension (I797) is still valid (before Feb 2022). Will I be challenged at port of entry whether i am going to perform the same duties as mentioned in I-129.<br>
3. To convince them on job responsibilities will the letter from employer be sufficient Or need something else?<br>
4. Recent pay stubs shall also be helpful to prove my continue employment with my same employer ?
5. H-1B extension (I-797) is expired (after Feb 2022) OR because of some reason I have to file new H-1B extension to enter Can i use my approved I-140 to file new H-1B extension(or claim the H-1B period) and that will be cap exempt ? OR I have to file new H-1B petition and re-enter the lottery.