dependent visa question

[otta]

hi . . i'm planning to apply hsmp, given that i meet the minimum requirements. the thing that i'm not sure is . . can i apply a visa for my spouse (unmarried partner) after i get the approval and settle down in the uk?

we've been living together for more than 2 years . . but what i'm concerned is . . if i'll live in the uk next year and my gf can't join my until the year after in order to finish her master degree . . would i have any troubles to apply a dependent visa for her ?

any suggestions would be greatly appreciated.