Correct. If you were on H1B and have I140 over for 6 months, you are exempt from cap. As long as you get approval notice from USCIS, you would be fine with consular processing. It’s nothing close to GC. If you’re not in the country, you need to find a company that can sponsor you H1B
Not for life. Only until your priority date becomes current. If your priority date is current for 12 consecutive months and you don't file I-485 then your I-140 gets cancelled and you are no longer eligible for post-6th year extensions.