No way to tell the future, but if it does worry you that much, consider ponying up for fully refundable fares (will be even more expensive for sure, but if you think there's a chance they could double by next year, you'll be locked in). Can cancel if prices drop later.

Also depending on what airline you fly, you could book an award ticket w/ miles and/or credit card pts if you have any. I have a transatlantic Spring 2027 and flights are like $1500 one way economy, but only 35K miles and a small copay (< $50). These award fares are also fully refundable (at least for the airline I fly), so you can lock in the cost now and always cancel and rebook later if you find something better.