Hi,
Usually it's not recommended to get married after getting visa grant and before validation trip (first entry). If it's possible and affordable to make a trip to validate your visa and come back and get married then this would be ideal. Anyways, in this condition you'll first have to inform your case officer that you're going to marry and ask him whether he-she allows you and confirm that it has no harm on your visa grant.
You'll have to download and fill
FORM: 1022-NotificationOfChangeInCircumstances.pdf
which can be downloaded from DIMIA web site. This filled form, medical and PCC of your wife and marriage documents will be required to send to your case officer through normal mail or courier. Remember, marriage certificate, your wife's medical and PCC is must to submit whether she is migrating with you or not.
Yes after validating your visa you'll be eligible to apply for a spouse visa for her.
Regards, M.Mateen.
P.S. Just for a suggestion, ask your case officer if you can still include her in your application? If there's any option at this stage then it would be another ideal :) as it'll save money + hbuttle of getting spouse visa. Believe me you'll have to provide a lot of things under the section which requires evidences of your genuine and continuing relationship.
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