Recurring RCBO (or RCD) tripping after a solar install is a known headache, and it's worth treating as a real electrical fault to be chased rather than something to live with. Sometimes it's a daily, predictable trip that resets and runs fine afterwards; other times it's intermittent. Either way, repeated tripping points to an underlying issue — a faulty or marginal protective device, an earth leakage problem, or interaction between the solar, an EV charger and the rest of the circuit.
A common fix is swapping the protective device itself — for example replacing one make of 30mA RCBO with an equivalent from another manufacturer — which can resolve nuisance tripping if the original unit was over-sensitive or faulty. Tripping also tends to cluster around specific events (an EV charger pulling power, or the diverter switching as solar becomes available), which helps pinpoint the cause. An electrician unfamiliar with solar may be wary of the setup, so ideally get someone who understands PV and battery installs to diagnose it.
The key thing is not to ignore it: an RCBO that won't stay on can cut power to your EV charger, stop the diverter using solar, and is protecting against earth faults for a reason. Notify your installer (it may be a warranty/snag issue), and if they can't find it, bring in an electrician comfortable with solar to investigate the earth leakage properly. Persistent tripping is a symptom worth getting to the bottom of rather than just resetting each day.