Ive trawled through a few pages but really cant find the answer i need and i appreciate things are changing daily. So here goes:

I need to travel to South Africa for business and the plan is to fly out mid june returning around the 7th July. Im looking to fly business with Qatar so ive been looking at the usual suspects, OSL, ARN, CPH, MAD, BCN etc. Ive found really cheap flights from Sofia, reasonable prices from Madrid but the main concern is coming home. Im looking to transit to Portugal on the way home but the issue i have is Qatar are not operating LIS>DOH the now so any flights mean i need to do entry to country before flying on

Im fully vaccinated with Astro and have my details on NHS app. Im happy to take all the tests needed etc.

I just need to know what countries could allow me to transit through and on within 24 hours without quarantine.

Any help would be so much appreciated.