Is it possible to lock a Solr Collection during a reindex?

TSIA.  I have a Solr Collection of questions asked by users (our own internal AUA).  Every time a user submits a question, the question is inserted into a database and the Solr Collection reindexed.

Just on the small chance that two users submit a question at about the same time, I don't want the second question to trigger a reindex until after the first question reindex is completed.  So is it possible to lock a Solr Collection each time it is automatically reindexed?

V/r,

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