There is a particular problem here for church building where the Usus Authenticus and the Usus Deterior of the Roman Rite are both in frequent use. It is distracting and unseemly to have the Candle standing in the Sanctuary ... and unlit.
Historically, there have been many different local usages with regard to the removal of the Candle. During the Gospel of the Ascension; after the Gospel on Ascension Day; after Mass, or after None, or after Compline, or at the eleventh hour on Ascension Day; the Friday after Ascension Day; the Wednesday after Ascension Day. But, in some places, we find: the Vigil of Pentecost; 'at Pentecost'; at Compline of Pentecost; or (at Worcester) on Trinity Sunday! Bishop Grandisson's rules at Exeter are not consistent: but in one rule the Candle remains until Pentecost.
And the Usus Authenticus itself has an ambiguity. If one celebrates the Vigil of Pentecost, one is supposed to bring the Candle back into use for that liturgical event.
Messy? A bit, surely.
Many will disagree with me; but I rather feel that the neatest solution in churches frequented by followers of both Uses would be to keep the Candle in use either until the Compline of Pentecost, or (so as to draw laudable attention to the Octave of Pentecost) until after None on the Saturday before Trinity Sunday.