Ryanair Holdings Plc may have to cut more flights from its summer schedule if the grounding of Boeing Co.’s 737 Max jetliner drags on, Chief Executive Officer Michael O’Leary said.

It’s possible Ryanair will have none of the narrow-body planes in its fleet for next year’s high season, according O’Leary, who said in a Dublin court on Thursday that deliveries of the carrier’s aircraft might not commence until April or May, or even the autumn.

Europe’s biggest low-cost airline said earlier this week it now expects to get just 10 Max jets for summer 2020, or half the number previously projected, a shortfall it estimates will wipe 1 million passengers from the full-year tally. Ryanair had originally planned to take 58 planes by then before repeatedly paring the estimate as the crisis surrounding the model deepened.

Questioned in the Irish High Court in a case concerning the departure of Chief Operations Officer Peter Bellew to rival discounter EasyJet Plc, O’Leary said he agreed that there is total uncertainty as to whether the Max will arrive at all by next summer.

While Boeing aims to get the Max flying again by the end of the year following a grounding prompted by two fatal crashes, Ryanair is due to be the debut operator of a high-capacity version requiring additional certification even when the baseline plane has made its return.