You can text them using wifi and ask them to text confirmation of new pick up time, so you know they saw it. Does your service provider not have international calling, even for an extra fee? For Ex, Verizon has a daily rate of $10 if you set it up in advance and it only charges if you use it. Texting is usually much cheaper than calling if you have to pay extra out of pocket without a plan.
Lots of how to pack advice websites. Here's our typical suitcase for 4 weeks, which also includes dressier evening attire--you can ditch that if not needed:
Me--4 dark bottoms: 1 cotton capri, 1 dressy pants/capris, 1 skirt, 1 bermuda shorts (summer) and also 1 sleeveless black knit dress, scarves (to change up the black dress), some silky/poly tops for dinner, cotton shirts, sleeveless shells, 1 3/4 cotton sweater. I mix/match adding chunky costume jewelry for dinner. 1 pair dressier (but comfy) shoes for dinner, 1 walking shoe, 1 black flats.
DH--3 bottoms: 1 khaki and 1 zip off trail paints, 1 bermuda shorts, 5 knit polos, 2 tee shirts, 1-2 dress shirts, 2 ties, 1 casual dress shoes, 1 low rise hiker