Is/was the first time

[Xinfu]

What's the difference between

-This is the first time I have given a suggestion.
-This was the first time I had given a suggestion.

HAVE GIVEN means the act is completed, then why IS not WAS? Assuming that the two sentences refer to past acts, what's the difference between is/was?

[poli]

What's the difference between

-This is the first time I have given a suggestion.
-This was the first time I had given a suggestion.

HAVE GIVEN means the act is completed, then why IS not WAS? Assuming that the two sentences refer to past acts, what's the difference between is/was?
There is a difference in meaning.
When you say the is the first time...., it refers to something done a short while ago.

This was...refers to something done a while ago, and probably done habitually or frequently since.

[Xinfu]

Thank you.