Can I bring Bikurim to the Beis Hamikdosh when I am Ole Regel on Shavuos?
Bikurim are not brought before Shavuos.
On the holiday itself, there are different opinions in the Rishonim as to whether it is permissible to bring Bikurim.
Mishna Bikurim chapter 1, Mishna 3.
See Tosefos Bechoros 26a s.v. Melay’ascha. Maharit Algazi ibid. Minchas Chinuch Mitzva 18. Sh’ut Igros Moshe Orach Chaim vol. 1 Inyanei Kodshim Siman 1.
Note: This law will become relevant with the imminent revelation of Moshiach.