SSRS Expression for FY Week Number

Hello from Australia, I hope someone can help me!

I have a report I run each Monday, and am using the below expression to return the current week number (based on FY beginning 01/07)

=Format(DatePart(DateInterval.WeekofYear,Today()),"00")+26

However I need to manually change the +26 to -26 (and vv) on the 1st Jan and again on 1st Jul in order to give the correct FY week number

Can anyone please suggest an expression that calculates based on FY, so I do not need to update manually every 6 months?

Thanks very much