Secondly, the patent should be "novel", that is, it cannot be known to the public before the filing date. If your utility model has been successfully applied, it will be made public, which means that the technology has lost its novelty. You can't apply for a patent anymore. Even yourself.
In addition, I think competitors are unlikely to apply for the same technology again, bypassing the scope of protection of the owner's rights. Because all technical details have been published in the specification, even if the other party changes the claim, the application cannot be successful, or even if the application is successful, the right is unstable.
In addition, if it is a very important technology, it is recommended to apply for both invention and utility model. This will maximize your own interests.