Distinguishing present from future in a conditional sentence

Question

Consider the following sentences, used in an email message:

I'm going to be on vacation next week. If you need anything, call me.

It could mean

1. If you need anything now, call me, because next week I will be on vacation (and may not be available).
2. If you need anything next week, call me, even though I will be on vacation (I will be available).

I don't see a way to distinguish between these two interpretations, unless there is some context. But this kind of message is often sent without context.

The problem is that the conditional statement uses present simple in the conditional part (as is usually prescribed for a "1st conditional"), regardless of whether the condition refers to the present or to the future. Other languages have different conditional constructions for these cases.

Translating literally from my native language, the way to refer to the future would be "If you will need anything" - but to me it sounds like really bad English.

Are there unambiguous ways to phrase this message with each of these possible meanings in good English?

Answer 1

You are correct that both meanings are possible, but I think the second meaning will be inferred by the vast majority of recipients. This is because the first sentence establishes a setting in the future (next week) and this setting carries over to the next sentence.

It is easy to explicitly select one meaning or the other by adding to the statement:

• I'll be on vacation next week. If you need anything while I'm gone, call me.
• I'll be on vacation next week. If you need anything before I leave / before then, call me.

Answer 2

1. I'm going to be on vacation next week. So if you need anything, call me before then.

   2. I'm going to be on vacation next week. But if you need anything, call me.