Conditional Formatting to react to Row Above while Ignoring Hidden Rows

I've been stuck on this problem for quite some time and have decided to ask for help.

At my company we have a large spreadsheet that shows various data for different projects over the last year. Each Project has a "Job Number" (Column A) and 12 rows representing the past 12 months (month displayed in Column B). The spreadsheet is sorted by Column A, then Column B, and so shows all projects in blocks of 12.

The people who use this spreadsheet often want to filter this to various months (eg, show all projects May-Jul) and so the borders set up between projects get hidden. They have recently asked me if there was a way to make it so that Excel always separates projects with a border line, to clearly define each project.

At first, I just wrote a basic conditional formatting rule where if Cell A did not match Cell A below it, then place a line between them. I forgot that, obviously, once this gets filtered, those rows will still be counted in the formula.

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TLDR;
What I'm looking for, is a way to place a border line between two rows where Column A is not the same, but to also ignore any hidden rows in between them.

Or perhaps I am missing the wood for the trees on this and there is a far simpler method that I am missing?

Any help would be massively appreciated.