I heard this during a conference call.

Problem:
The number of the verb does not match the number of “a number of updates”.

Explanation:
The phrase “a number of updates” is singular (because “a number” is singular).

In contrast, the “were” form of the verb “be” is third-person plural.

The solution is to use the third-person singular form of the verb “be”.

I believe that the problematic sentence is an example of speakers and writers being distracted by the noun “updates”, which is plural and ends the sentence (and therefore tends to get more attention than does “a number”).

Solution:
“There was a number of updates.”