Bulgaria and Poland are quite a ways away from the UK.
Distance from Bulgaria to UK is: 1250.7 Miles( 2012.9 Kilometers / 1086.1 Nautical Miles )Approximate flight duration time from Sofia, Bulgaria to London, UK is 2 hrs, 36 mins
UK city Hull. It will take about 4 hours, with a over stop at Heathrow
Postal mails (even ordinary, Par Avion) may reach fast from UK to Bulgaria. As there are many flights from London to Sofia per day. The question is from which part of UK is the mail and to what destination is to reach in Bulgaria. Overall 5-7 working days would be good enough. Priority and Courier mails reach faster.
Devon - UK Parliament constituency - ended in 1832.
Devon - UK Parliament constituency - was created in 1290.
Charter flights and seasonal flights are direct and one stop. Regular flights are with transition. Manchester-Heathrow-Sofia-Varna
East Devon - UK Parliament constituency - was created in 1868.
East Devon - UK Parliament constituency - ended in 1885.
North Devon - UK Parliament constituency - was created in 1832.
North Devon - UK Parliament constituency - ended in 1885.
Which US State? Please specify. Bulgaria is 111,000 sq. kilometers. Thw questioner now can compare this terrioreal size of Bulgaria with any US state (providing having knowledgge of the sizes of the US States)