Reddit won’t limit how many accounts you create, at least not until they detect something suspicious. I think your idea of toggling airplane mode to refresh the mobile IP is pretty clever. I actually used a similar method for creating Gmail accounts without phone verification. But by the fourth attempt, Google started asking for a phone number, which probably meant the new IP I got was already flagged or reused too many times for account creation.
So yeah, mobile IPs do rotate, but that doesn’t always mean they’re clean. And another thing, if you’re using the same device for too many accounts, Reddit might eventually pick up on that as well, especially if your behavior patterns look automated or too similar. It could lead to mass bans.
If you plan on creating dozens or even hundreds of Reddit accounts, I’d honestly suggest using an antidetect browser like GoLogin, Hidemyacc, or similar, paired with clean proxies. It’s not only safer in terms of fingerprint separation, but also much easier to manage than juggling multiple browsers on one phone.
Got multiple devices? 
