Just as the first Redeemer (Moshe) was revealed and then concealed from them [the Jewish people], similarly, also the final Redeemer will be revealed to them [the Jewish people] and then concealed.
(Bamidbar Rabbah 11:2)
The term revelation of the true and complete Geulah through Moshiach (in the Midrash cited above) is consistent with the term used by the Rambam (Hilchos Melochim end of ch. 11): “B’Chezkas . . . b’Vadai” (“consider with assurance . . . he is definitely Moshiach” (Likkutei Sichos vol. 9 p. 381)
There is no indication to suggest that the Rambam does not support the idea that Moshiach will be revealed and then concealed.
This can also not be suggested from the Rambam’s proof regarding Ben Koziva, [that Rabbi Akiva and all the Sages of his generation considered Ben Kosiva to be King Moshiach], because Ben Koziva was actually concealed for some time (in caves) during his battles
(Likkutei Sichos vol. 9 p. 105)
