الصيانة هتبدا بكرة الصبح.

A good rough pronunciation is eṣ-ṣeyāna hatibda bukra eṣ-ṣobḥ.

Very roughly for an English speaker:

• الصيانة → es-seYAna
• هتبدا → ha-TIB-da
• بكرة → BUK-ra
• الصبح → es-SOBH

Two helpful notes:

• In الصيانة and الصبح, the الـ sound blends into the ص, so you hear something like eṣ-ṣ..., not a clear el-.
• هتبدا is often pronounced without a strong final glottal stop in everyday speech.

In Egyptian Arabic, هـ at the beginning of a present-tense verb is a common future marker. It usually means will or is going to.

So:

• تبدأ / تبدا = she/it starts
• هتبدأ / هتبدا = she/it will start

Here, هتبدا means will start.

Because الصيانة is a feminine noun in Arabic.

The word صيانة ends in ـة, which is a common feminine ending, so the verb agrees with it:

• هيبدا = he/it will start for a masculine subject
• هتبدا = she/it will start for a feminine subject

Even though maintenance is not biologically female, Arabic nouns still have grammatical gender.

Because Egyptian Arabic allows both patterns:

• الصيانة هتبدا بكرة الصبح
• هتبدا الصيانة بكرة الصبح

Both are natural. Starting with الصيانة makes maintenance the topic, something like:

• As for the maintenance, it will start tomorrow morning

So this version can sound slightly more topic-focused or context-linked, especially if everyone already knows which maintenance is being discussed.

الصيانة means the maintenance. Arabic often uses the definite article where English might simply say maintenance with no article.

Here, the speaker is probably referring to a specific, known maintenance operation, such as scheduled building maintenance, internet maintenance, road work, and so on.

So:

• الصيانة = the maintenance / the maintenance work
• صيانة = maintenance in a more general or indefinite sense

That is very common in informal Egyptian writing.

In more careful spelling, you may see هتبدأ, with the hamza. But in everyday texting and casual writing, many people write هتبدا and leave the hamza out.

So:

• هتبدأ = more careful spelling
• هتبدا = very common casual spelling

They represent the same word here.

It means maintenance, but in real-life use it can also mean:

• maintenance work
• repair work
• servicing
• scheduled maintenance

The exact English translation depends on context. For example, if this is a notice in a building, on a website, or from a company, maintenance work is often the most natural interpretation.

Yes, literally it is something like tomorrow, the morning, but idiomatically it simply means tomorrow morning.

This is a very normal Egyptian time expression:

• بكرة = tomorrow
• الصبح = the morning / in the morning

Together:

• بكرة الصبح = tomorrow morning

Arabic does not need an extra word like in or on here.

No. With common time expressions like this, Egyptian Arabic usually does not need a preposition.

So this is natural:

• الصيانة هتبدا بكرة الصبح

Adding في would usually sound unnecessary here.

This is similar to English, where we also say tomorrow morning without a preposition.

Yes, this is natural Egyptian Arabic.

A more Modern Standard Arabic version would be something like:

• ستبدأ الصيانة غدًا صباحًا
• or الصيانة ستبدأ غدًا صباحًا

Main differences:

• Egyptian هتبدا → MSA ستبدأ
• Egyptian بكرة → MSA غدًا
• Egyptian الصبح → MSA صباحًا

So the sentence you were given is clearly colloquial Egyptian, not formal written Arabic.