Far as having a 5 year cushion left before the 1.5C temperature rise line is crossed, I doubt even if we stopped cold turkey today, it would still be crossed. There's enough CO2 being released every year from forest fires to get the job done without burning the oil. 1.5C is arbitrary anyhow, we have enough climate problems already to have made large swaths of the available land mass less able to support their current populations, that's why we have so much migration going on. It will get worse of course, but it's bad enough already. Just check out the the homeless camps and shelters in any "sanctuary city" in the FSoA and Europe.
The Point of No Return has already been passed. excluding some spots from more drilling won't save the planet.
"Take one last look at this Sacred Heart
Before it Blows
Because Everybody Knows
Everybody Knows"
https://www.newsweek.com/global-warming-oil-regions-temperature-rise-1880296
Map Shows Oil We Must Leave Alone to Avoid 'Irreversible' Climate Change
RE