The first thing is to do 'map recon' ~ identify what is covered terrain and approach routes, where he'll first 'get eyes on' your troops, *if he is place*, where you would set up several schemes of defence ~ with a view to blocking both the obvious direct approaches and any 'covered' route you identify.
Identify where you can establish an OP which gives good coverage of his rear areas ~ this gives information on moving elements ~ often it will observe activity at his Supply Bases, and may spot the shoots of his heavy artillery. You will also get early sight of his concentrating (ideal) or moving reserves, which should be disrupted by artillery to delay their arrival in the 'fight'.
Now look for covered routes for your supply lines ~ these need to be internal both 'before' the attack launches, during if it stalls, and after once concentrating on the objective and holding against his building counter-attacks... these may be contradictory, and might force a lateral movement of the Regt Bases in your rear area to support each force without lateral movement of the truck columns in the FEBA.
Identify covered areas for your artillery, close to the enemy FLOT, but with their minimum ranges clear of their positions ~ particularly in that scenario, where little ammunition is immediately on hand you can displace a proportion of the artillery forward to support in depth on later days, and to provide a local 'emergency' AT and direct fire support during the recovery phase of the initial assault. 105mm HEAT is quite effective at breaking up light armour counter-attacks.
The infantry must assemble and commence their assaults from out of sight ~ trying to throw together an attack in the open, in broad daylight will fail. You can use dead-ground, terrain cover (woods and buildings) and night/bad weather to do this.
With a good 'map-work' and a fairly heavy preparation on the forward edge of the objective, plus heavy fires to suppress anything seen in depth, and you should be able to storm Hofen in the first assault, and hold it from the counter-attacks.
You can infiltrate small bodies of troops between or around his defended areas, and provide targets for artillery on subsequent days ~ with luck you can displace or eliminate some or all of his supply and artillery. This isn't always a *good* idea, but when it works out it almost always pays off ~ even if only in tying down a lot of enemy firepower and combat strength trying to eliminate the threat.
Look at the battlefield from the enemy point of view too ~ look for his lines of supply and reinforcement, and place fires and observation across them... this will force him to either fight with steadily declining supplies, or to move from his trenches to attack to re-open them. Any time you can make him move, rather than sit tight on the objectives you get an opportunity to disrupt one or more units with artillery, or an ambush... turn the tables on him.
Although you are the "attacker" you can actually spend much of the scenario 'dug-in' on the objectives, forcing him to attack in the open to get them back. Where possible an attack should also block entry (and exit) to the objective area ~ this makes it harder for your opponent to feed more troops in, and increases the number of prisoners you'll take from anyone who does retreat or rout from the battle. This shouldn't take too much combat power from your main attack (or it will fail), but it is a good use for those units which perhaps are a bit 'spent', particularly if leavened with Artillery and A/T support when required.