An Australiana Puzzle

Across

1: Tuition cost first negotiated, arranged and passed in UK for us (12)

5 & 49 across: “F” as assembled 230 or so years ago (5,5)

10: Somehow anoint Robin to achieve this at 23 down (10)

14: One day star, regrouped, now he's fallen from grace (8)

16: Suggestions Prime Minister and politicians worked together ... (12)

17: ... a long speech, with new decrees but lacking direction (6)

19: Remodelled Stanton Airport could provide this! (14)

20: Some sailor caught a whale (4)

23: The part of a falafel on stage taken by 1 downs? (6)

25: Dad rebuilt annex (3)

27: Emu held in empty pool starts waddling up. Yes, he fought newcomers bravely (8)

29: Dreadful biocidal panic! I lob Aida back inside (8)

31: Choose some helicopter (3)

33: Best land to cast seed on in a parable (6)

37: Trick an early Aussie farmer (4)

38: New pupils endured 5,49 problem (13)

42: English included in “New Maths” or the same arrangement without English? It's more than just a major English stream (6)

44: What you have if you combine leaderless 14 with a dual citizenship occasion (9,3)

46: Arrange to see the assembled Eora sing (8)

47: Lockup replaces first prison in former coppers noted accomplishment (10)

49: See 5 across

50: Redesigned Perth penthouses - but colourless harbour (4,8)

Down

1: Some emoticon victim subjected to 19 (7)

2: Crops it adapts for hot and humid zones (6)

3: Sounds like you know this game (3)

4: Outbid Crohns and Colitis? (3)

6: Complete with new traction - or not (6)

7: See 12 down

8: Flinders' companion in ACT Assembly (3)

9: Arrange inward force unit for early resister (10)

11: New patois first language raised on 5,49 (7)

12 & 7 down: GG shot, a defeat revamped (4,2,5)

13: Left out MC not committed

15: Some hank not seen in 18 on 5,49? (5)

18: Lines used on 5,49 - Europe's lost domain  (5)

21: Argue in dinghy? (3)

22: Some rises in corrupt activities. Hear it from 8? (4)

23: Federer's elation disheartened when 1-across took effect (10)

24: “A” time either way (4)

26: Musical pair in loud comeback (3)

28: Takeaway? Would require some vitamin use! (5)

30: No first pass for fool (3)

32: Fee not paid by 5,49 in Sydney (4,3)

34: Begins by uploading info. Loaded database okay? Now continue construction (5,2)

35: Disgust felt when first presenter left podium (5)

36: Outrage not right! This was due to storm damage (6)

39: Sounds like a boost for Arthur (7)

40: For Naps these are terribly bad dyes (7)

41: An other-side encounter occurs every second as her aunt Cher shows (6)

43: Some sang elegies, one heaven sent (5)

45: How do you find out what is kept in a basket? (3)

47: Make a mistake in claiming Terra Nullius (3)

48: Let us sound out the chief of staff (3)