Mdadm: no devices listed in conf file were found – Debian 8 with GPT

I have a Debian Jessie (3.16.7-ckt20-1+deb8u3) system with RAID1 on 2x 3TB hard drives. Grub can't be installed into MBR on drives >2TB, thus I have GPT with 1MB bios partition:

Device          Start        End    Sectors   Size Type
/dev/sda1        2048       4095       2048     1M BIOS boot
/dev/sda2        4096 1953128447 1953124352 931.3G Linux RAID
/dev/sda3  1953128448 5860532223 3907403776   1.8T Linux RAID

After rebooting (kernel upgraded deb8u2 -> deb8u3) system ended up in initramfs rescue:

Loading, please wait...
mdadm: No device listed in conf file were found.   

Gave up waiting for root device. Common problems:
- Boot args (cat /proc/cmdline)
  - Check rootdelay= (did the system wait long enough?)
  - Check root= (did the system wait for the right device?)
- Missing modules (cat /proc/modules; ls /dev)
ALERT! /dev/disk/by-uuid/5887d2e0-bae1-4ce8-ac6f-168fb183d7b0 does not exist.
Dropping to a shell!
modprobe: module ehci-orion not found in modules.dep

BusyBox v1.22.1 (Debian 1:1.22.0-9+deb8u1) built-in shell (ash)
Enter 'help' for a list of built-in commands.

/bin/sh: can't access tty; job control turned off
(initramfs) 

From the console I'm able to check that the RAID array seems to be OK:

 cat /proc/mdstat 
Personalities : [raid1] 
md2 : active raid1 sda3[0] sdb3[1]
      1953570816 blocks super 1.2 [2/2] [UU]
      bitmap: 0/15 pages [0KB], 65536KB chunk

md1 : active raid1 sda2[0] sdb2[1]
      976431104 blocks super 1.2 [2/2] [UU]
      bitmap: 0/8 pages [0KB], 65536KB chunk

unused devices: <none>

the missing disk is the md1 device which is not present in /dev/md/ with root partition. Also config file /etc/mdadm/mdadm.conf show same content as mdadm --examine --scan:

$ mdadm --examine --scan
ARRAY /dev/md/1  metadata=1.2 UUID=c366b4e9:e33d2b69:3c738749:07b022c6 name=w02:1
ARRAY /dev/md/2  metadata=1.2 UUID=c32939b8:bc01f4ff:b85f00c6:b50aa29e name=w02:2

Using mdadm --examine /dev/sda2 I've check that all RAID partitions are in clean state (AA). Is there something more I can do?

Can I try to continue in manual booting? How to do that? How would I increase rootdelay= for next reboot? (the system waited for the right device, it's not the second suggested problem).