I wouldn't be surprised with how market reacts because it's unpredictable short term. You're going to regret few years down the road for going in and out position now and realize later that you were better off just staying invested and adding more money whenever you can.
It's better to just continue to accumulate asset and eventually, it will start snowballing as your asset will become massive.
Also, investing in airline stocks, I'm not sure I see the upside. I think you may be able to get a quick gain, but long term, I think it will underperform compared to investing in great companies from like FAANG or companies like Salesforce or Chipotle.
I used to be like you of jumping in and out, as well as buy stocks that's been beaten down thinking they're good values. They're good values for a reason.
It's similar to how cost of living in great places like Southern California is expensive. It's expensive for a reason. It's awesome and will continue to be desirable so wouldn't be surprised if cost of living continues to climb. You can get great value living in places like Indiana. But it's cheap for a reason and will never get expensive to live there as if it gets too expensive, there are plenty of alternatives where it's cheaper to grow. So, my analogy is that don't be afraid to buy stocks that seem expensive like Amazon as there's great chance that it will continue to climb as it will be desirable stock 10, 20 years from now.