Pomona, CA notice for renewal with rent increase tied to CPI

[Tiprin Lujan]

How do you all give notice for rent increase and lease renewal in advance if you don't know what the CPI will be?

My local ordinance in Pomona, CA caps rent increases at the lesser of 4% or the percent change in CPI for the period before the effective date of the increase. Rent will increase in August and the June CPI won't come out until Aug 13th. I prefer to give renewal letters 60 days in advance.

Link to Ordinance:https://www.pomonaca.gov/home/...  

Link to CPI-U: https://www.bls.gov/regions/west/news-release/consumerpriceindex_losangeles.htm

I was thinking of adding a line in the renewal letter stating that the property is subject to this ordinance and rent will be adjusted if necessary. If the CPI is lower than 4% I would give the tenant a refund for the difference. Just curious if anyone else is doing this.