subjunctive mood - Using the present tense to write about future events as future events

I'm an undergraduate student. Today, I was writing an email to my department's undergrad adviser to request a meeting to discuss what I will study next year. When I began to write the email, I wrote

Dear Dr. X,

Next year I complete the final year of my program.

When I read it aloud, it sounds right. However, I'm writing about an event in the future, and so I believe that I should have written

Dear Dr. X,

Next year I will complete the final year of my program.

However, the use of will seems to make the sentence more presumptuous.

I suspect that the first version is written subjunctively*. However, to the best of my knowledge, subjunctivesque constructions that resemble the first version are typically imperatives, and typically follow that. For example, 'It is required that she arrive before noon tomorrow.'

Is the first version grammatical. If so, why is it so; if not, why is not grammatical?

(Note: I asked this question in order to learn about English. I did not intend to ask for advice on what I should write in this email. Accordingly, I would prefer a answer that explicates the relevant grammatical, or linguistic, principles. Thank you.)

Answer

The first version is fine: see past questions (and their answers) regarding Simple Present for Future Actions and Present tense for future events for more information on the use of present tense in this way.

The notion that your second version is more presumptuous may arise somehow from the old shall/will usage distinction in the formation of the future. On that see When should I use “shall” versus “will”? Briefly, according to the old-fashioned distinction outlined in the 2nd (Ernest Gowers) edition of H. W. Fowler’s Dictionary of Modern English Usage, forming the first-person future with will implies special certainty and/or iron determination, shall being the default modal for first-person futures. (This was only ever a thing in British English, I think.)

Finally, to complete the final year of the program is to complete the program, right? So there is a possible opportunity to trim four words without loss of meaning.