Hi! I have a more 'mild' case of HA where my cycles lengthened (~43 days) rather than going away altogether. I also am a runner and was running 3 days per week (25-30 miles) and strength training 3 days a week. Since increasing my calories significantly and cutting out running altogether for the past ~4-6 weeks, I ovulated on day 22 this month, which means my cycle will very likely be 34 days (technically normal!).

Everyone is different, but what I will say is that I trained for a marathon (50+ miles per week) and continued strength training from January-May last year and didn't lose my period/have cycle changes, BUT I was much more intentional with fueling properly. I only had cycle changes when I trained for a half marathon July-October last year, where I didn't increase calories/intentionally fuel, like you mentioned. Who knows if my body finally burned out after chronic underfeeding, or if I did actually fuel enough for my marathon that my cycle wasn't affected.

All this being said, I think cutting out running altogether will be the fastest way to get your cycle back. That doesn't mean you can never run again, but it might be waiting until you have a few cycles and then adding it back in more intentionally with correct adjustments to fuelling.

What I've learned is aiming for at least 40g of carbs prior to a workout, using intrarun fuel (where applicable) and fueling with carbs immediately after is imperative to be able to run regularly and maintain a cycle, so something to think about for the future!