You can edit the plugin’s default-template.php, but you might come across other unforeseen issues. So do it at your own risk.
In the above mentioned file you need to update the below values per your needs:
.splash-button-area {
margin: 400px 0 0 600px;
}
I’m facing an issue with 5.5 and Ocean Extra too. The header logo disappears from the homepage when ocean extra is enabled (but it still shows up on the other pages).