The two teams had been due to meet at Mousehole's Trungle Parc on Saturday, but the game was called off after referee Ben Judd failed to show.
South West Peninsula League secretary Phil Hiscox ordered that the game be replayed on Easter Monday, but with the county cup finals set to take place on the same day the Cornwall FA have vetoed his decision.
In a statement released this afternoon, Hiscox said: "Please be aware that as per Cornwall County FA rule 10, I have been advised that Cornwall FA are not able to sanction the playing of a game in Cornwall on Easter Monday.
"Therefore I have had to come up with alternative arrangements to get the match re-played and in doing so avoid all the previous problems highlighted of sheer amount of games, travel and the closing date of the season etc etc.
"The Cornwall FA have agreed to order the postponement of the Trelawny League game, Mousehole Reserves v Holmans at Trungle Parc on Saturday 26th April and therefore on that day Mousehole will play Vospers Oak Villa, 3pm at Trungle Parc.
"The reverse fixture, Vospers v Mousehole, will now be Sunday 27th April, 3pm at Weston Mill, thanks to the co-operation of the Weston Mill Social Club. (If a different kick off time is agreed I will sanction within reason)
"Whilst clearly not ideal to be using a Sunday it is unavoidable and whilst it is clearly also not ideal to play two games between the same two teams on two days running, the only Sundays left are 20th April which is Easter Sunday, 4th May which is no good as both teams are already playing on Saturday and Monday ! 11th May would clash with our own Cup final, the Throgmorton Final, and if its good enough for CCFA then it has to be good enough for us !"
Hiscox added: "I do not bear any grudge to any of the parties and circumstances that have conspired to cause me three days of non-stop work on arranging one fixture, but clearly I would appreciate the co-operation of ALL parties in putting in place these new arrangements."
Cornwall FA chief executive Dawn Aberdeen reacted to Hiscox's statement, saying: "Cornwall FA highlighted the two fixtures Mousehole v Vospers Oak Villa on Monday 21st April and the fixture on Saturday 26th April Vospers Oak Villa v Mousehole which could easily be reversed with which you agreed, also noting that Vospers did not have a reserves team and that therefore this amendment only affected the Mousehole reserve fixture which I said I would discuss with that respective league.
"This seemed a common sense solution to an issue which could have been avoided and I do not understand your response following our discussion."