The club says it will lose home advantage and it does not accept the league's decision.
Guernsey FC says it was informed late on Bank Holiday Monday (4 May) of the decision by the Southern Combination Football League (SCFL) to move the venue for the play-off final from Guernsey's Victoria Park on Sunday 10 May to the UK, mid next week.
The SCFL cited travel difficulties for opponents Peacehaven and Telscombe but Guernsey FC say they have been trying to help the club get to Guernsey for the Victoria Park final.
Guernsey FC had been looking forward to the showpiece being held in front of a home crowd and says it earned that right.
It says moving the fixture to an unspecified UK venue next Tuesday or Wednesday undermines the integrity of the competition and is a position the Club does not accept.
It has been in dialogue with the SCFL but so far has not reached a compromise.
Guernsey FC says it is considering its options including a formal appeal to the FA.

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