B-1 Visa

I have just 50 days left on my H1B grace period, and I need to get an employer to transfer my H1B, or I will be kicked out of the States. My question is, which of the following paths should I choose?

1) I have a Canadian visitor visa, which is for six months, so can I go to Canada if I don't get a job by the grace period?

2) If I don't get an employer should I shift on B1/B2? If I do, how can I come back on H1B? Is there anything else you suggest to keep my H1B active?

I have a question about my mother's stay in the US on a visitor (B2) visa. I am an IT Professional in the US on an L1 work visa along with my family (spouse & kid). My only sibling (younger sister) is also settled here in the USA. My father passed away a couple of years back in India. My mother is 60+ years of age, and currently, there is no family member in India to stay with her at all times. She visits the USA and stays with us for six months at a stretch during the year. Considering her health and emotional support needs, I am looking for options to have her stay with us long-term (beyond a six-month period in a year). As is the case in this scenario, are there legally valid options/exceptions for old-age single parents?

1. I am currently in a 60-day grace period due to a layoff and am in the process of finding a new employer to file an H1B transfer. I have two questions regarding my situation:
If I apply for a B1/B2 visa on the 59th day of my grace period and it is approved within two weeks, can my new employer still file an H1B transfer using premium processing? 

2. Specifically, I am concerned about the impact of my status change from H1B to B1/B2 and then back to H1B on the processing of the transfer.

3. My family members hold a valid US visa stamping until March 2027, which was obtained using my previous employer's I-797. Can they enter the US using this existing visa with a copy of my new employer's I-797 at the port of entry?