Need legal & practical advice about defaulting on apartment installments in Egypt — should I continue paying or return the unit?

Hi everyone,
I need advice (legal + practical + from real experience) regarding a problem I’m currently facing with my apartment installments in Egypt.

Summary of the situation:
I bought an apartment exactly one year ago for 3.5M EGP, paid 700k EGP down payment, and the remaining amount is on installments until 1–1–2030.
The first installment was paid on 1–4–2025 (105k EGP every 3 months).
So far, 3 quarterly installments were paid = 315,000 EGP.

Now I’m required to pay:

166,625 EGP today, and

189,500 EGP on 30-12.

The agreement between me and my father was:
He would pay each installment on its due date (because we work in the same company and salaries are usually delayed for 4 months). When my salary is released, I repay him the exact amount he paid.

My plan was based on earning $1500/month, with $500 automatically going to my father’s account, plus I would send him another $500, meaning I’d repay $1000/month (~48k EGP/month on average) for the full 58-month period.

But recently my father told me he no longer agrees to this system. He wants to settle year-by-year because he might stop working, and if that happens, he wants all the money he paid back immediately — and I will be responsible for all future installments myself.

I told him that if I had known this earlier, I wouldn’t have bought the apartment because my salary schedule doesn’t allow me to commit to fixed installment dates mentioned in the contract.

Now the discussion ended with:
Maybe the best option is to return the apartment altogether.

My Questions:
1️⃣ Should I pay the two upcoming amounts (166,625 now + 189,500 on 30-12)?
Or should I contact the developer in January when I return to Egypt and request to return the unit?
If I return the apartment, they will deduct 10% of the total property price (350,000 EGP) no matter how much I’ve paid — and refund the rest.

2️⃣ What is the BEST solution based on Egyptian real-estate law + real experiences?
These are the options I’m considering:

Option A — Continue paying for now
Even if I plan on returning the unit later, staying committed to the contract strengthens my legal position. If I ever negotiate a full refund without the 10% deduction, being up-to-date helps.

Option B — Sell the apartment to someone else
Basically:
The buyer pays me my down payment + installments I already paid, plus a small overprice, and they continue the remaining installments.
But I’m not sure:

How allowed this is

Whether the developer needs to approve

If I can finish the sale before the next installment in March (because I won’t be able to pay it if my salary hasn’t been released)

Option C — Swap the apartment for another one in the same project
One that equals the amount I’ve already paid (or with a very small difference).
But I don’t know how flexible developers are with this.

What would you do? What is the most logical + legally safe solution in Egypt?
I’d appreciate answers based on law, real cases, or experience with developers.

Thanks in advance